1. Field of Invention
This invention relates generally to systems for mounting solar panels or photovoltaic cells and more specifically to ballasted roof mounted racking systems for mounting photovoltaic cells.
2. Discussion of Related Art
Solar energy provides the opportunity to generate electricity without consumption of fossil fuels and is considered clean technology. In recent years, the development of technology for solar thermal systems and photovoltaic systems has improved the overall viability of solar energy. Increasing prices of fossil fuel and the prospect of expending world oil reserves has created a demand for alternative energy sources that can supplement and/or replace some of the energy needs consumed presently by fossil fuels. Thus, the demand for solar energy has increased. Because of the overall accessibility of solar energy, individuals or small businesses can own and control all or a significant portion of its energy production free from dependence upon the power grid. With the advances of electric powered automobiles, even transportation needs can be met by solar generated electricity. Presently, solar power technology is one of the most widely-accessible form of alternative fuel to the general population of the world. All is needed is access to direct sunlight.
The cost of solar panel technology includes not only cost of the photovoltaic panels, but a significant investment installation equipment and the labor to construct a solar electric system. Thus, a technology advance that reduces the cost of installation of photovoltaic modules (whether through reducing material cost, shipping costs, or labor costs) makes photovoltaic technology more viable and attractive from an investment perspective. The quality of installation also affects the efficiency of solar panel installation. The direction of the solar panels relative to the sun, the angle of the solar panels relative to the horizon, the density of solar panels in a given area, as well as position of solar panels relative to other panels can have a positive or negative effect on performance of the solar powered system.
A large percentage of commercial solar panel systems are installed on generally flat roofs of office buildings. Generally flat means that the roof is designed to be generally horizontal without a predefined pitch. It should be understood that while generally flat, flat roofs are often uneven due to settling of the building, construction imperfections, etc. A flat roof structure is an attractive place to locate a solar panel installation because there is often a large surface area of unused space with relatively few obstructions of sunlight. The traffic on a roof is typically restricted. Because access is restricted, the likelihood of intentional or accidental damage or theft is naturally reduced with relatively inexpensive safety precautions. Consequently, there is a significant effort in the solar panel industry to design effective flat roof mounts or racks to support arrays of solar panels on flat roofs.
The ability to assemble with one additional row of solar panels without causing overlap of the solar panels in sunlight or compromising optimal positioning would be a great advantage. Moreover, it would be advantageous if photovoltaic panels could be installed by an unskilled laborer or layperson (do-it-yourselfer) without a lot of formal training. It would be further advantageous if the system could be installed by hand without tools. It would be further advantageous if the product was light-weight, could be stacked or configured in a compact manner to ship a larger number of system components per unit of shipping volume and thereby reduce shipping costs. An additional advantage would be to have a system that can be easily adapted to avoid obstructions in the roof such as common rooftop fixtures without having to cut and resize parts of the solar panel system. Reducing installation time reduces labor cost making solar technology more accessible to the common individual.
U.S. Patent Publication 2008/0210221 to Genschorek discloses a relatively compact frame assembly that mounts solar panels at an angle for mounting on a flat structure such as a roof or ground. The metal frame system is supported by carrier profile elements with feet having holes forming connections to connect the carrier profile elements to the ground or roof surface—presumably by bolt, screw or penetrating fastener. The system has multiple parts requiring factory or on site assembly—potentially increasing product or installation cost.
U.S. Pat. No. 8,281,524 to Hund is a stackable wire frame design. The wire design is relatively lightweight, compact and stackable. The system is designed to have one framework support one panel so the system does not have the benefit of interconnectedness. Furthermore, the system is made from a wire grate connected by welds at wire intersections. It is pressed into the desired form. The wire is potentially vulnerable to damage by bending, corrosion, or breakage at weld points.
U.S. Pat. No. 6,105,316 to Bottger discloses an injection or blow molded device for supporting solar panels. The device has a bottom wall and a rear wall and two side walls integrally joined. Concrete blocks are place in the interior of the device. The solar panel is fastened to side edges of the bottom wall and rear wall. Each device supports a solar panel individually. There is one vertical member for each side. Thus, the panel array is not structurally interconnected.
U.S. Publ. No. 2006/0196128 to Duke discloses a mounting for solar panels with fixings on the front and side that enable it to be easily attached to other mountings for solar arrays. The devices are interconnected and stackable.
U.S. Publ. No. 2012/0036799 to Kneip discloses an injection molded support device that is compact and stackable. The height of the base is greater than its width and thus top-heavy relying upon the panels for side-to side stability. Thus, the device could have improved stability from side to side. Each device potentially supports one side of two adjacent panels.
U.S. Publ. No. 2012/0223032 to Rothschild discloses a solar panel mounting system of injection molded bases that are designed to support the panels at their respective corners. The bases can be nested like buckets for easy transport. Each device potentially supports four panels. Each bucket has four side walls.
Additionally, there is a need for systems that are lighter weight, easier to install and can be transported and lifted to rooftops with greater efficiency because a greater number of units can fit on a similar size pallet.
Thus, there still exists a need for a system that has many of the needs expressed above. The present invention addresses these and other needs.